Somehow, the default role 'subscriber’ was removed and set as administrator.

There were hundreds of fake admin accounts in kevinellerton.com and a few in meditationuniversity.us

To fix this -

Ved set the default role as subscriber using plugin "User Role Editor"

Setting -

"User Role Editor" -> default Roles -> Primary default role : subscribers

Pages from where users get register in system -

/wp-login.php?action=register

/affiliate-area/

/affiliate-register/